A new week begins on Saturday. Calm after the emotional rollercoaster of a political week culminating in my Friday evening constituency advice surgery in Twickenham. About par last week. Homeless family: three kids. Two asylum seekers whose papers are lost in the black hole of the Home Office. A woman whose pension has disappeared in a bureaucratic maze. Unfair parking fine. Local hospital horror story. Mr Angry who wants something done about next door's house extension. Ten others, including a young woman who thinks an MP is the best person to help her get a breast enlargement.

After breakfast, settle to a pile of correspondence, helped by my favourite bits from The Magic Flute. Not for long. Help is needed setting up a local party fundraising do that evening. Wife Rachel needs, and deserves, TLC after hundreds of calls to members drumming up support and making desserts. Then a large pool of water appears under the washing machine. Where are the Polish plumbers when you need them? Rachel and I perform DIY. Party organiser sounds desperate: immediate help needed to deliver food and raffle prizes. I tell him that Man Utd v Arsenal starts shortly. Fantasise about how Stalin would have dealt with the situation. Reflect on the merits of big, dodgy donors.

Function goes well despite everything. An eighth of one of Rachel's cows, which she farms in the New Forest, attracts high bids in the Dream Auction. Not all Lib Dems are vegetarians. Dinner is, however, interrupted by Sky camera crew and Five Live radio car wanting instant response to story about overpaid, undertaxed fat cats. Bad thing. Politics has taught me not to overcomplicate issues.

We go home happy with enough money for the next three leaflets. Late-night call from younger son, Hugo, in Louisiana. He's worried about his future as a theoretical physicist. I suggest returning to London to make a fortune as a mathematical 'quant' in the City. Not that desperate, Dad, he says.

Sunday starts with grandparenting. Young Charlie arrives, plants a kiss and disappears, beaming, into granddad's Aladdin's cave of toy cars and Lego. Only reappears when my daughter Aida, a supermum, whisks him off to delight another doting grandparent. We then move furniture and set up dustsheets for Bob the Builder who is due to knock two rooms into one. Hopes of reaching an oasis of quiet are dashed by call from party press office. Northern Rock nationalised. Get down to TV studios, pronto. Driving to Shepherd's Bush the mobile rings continually. Am tempted to answer, but saved by imagined headline of MP in dock on dangerous driving charge.

I assumed the government would sell to Richard Branson. Wrong. They did the right thing in the end - the least unsatisfactory way to safeguard taxpayers' money. Vindicated, though colleague texts to warn me that I am saying: 'I don't want to crow about this' too often. Mustn't sound smug. Try harder to be statesmanlike.

The media round goes well. Channel 4 News sends a crew to Twickenham and they eventually find an angle between the dustsheets. A far cry from the days when I sweated blood to get a passing mention in the inside pages of the Richmond & Twickenham Times. But fame comes at a price: missing a visit to my other grandson Ayrton and his Slovakian granddad and missing my Sunday dancing class.

Media frenzy continues at 6am with GMTV outside my front door. Minus five degrees and a baffled milkman worried about the strange goings-on at 102. Kate Garraway talking to me about banking rather than dancing while I blow frozen breath into the camera. Surreal experience ends with car to whisk me to Today and new media round.

Back home for a visit and photo opportunity at a post office in Teddington threatened with closure. First law of politics: the constituency comes first. Not to mention numerous Lib Dem workshops on the importance of communities and the political ground war. Cross producers in the media centre have to wait for the air war to recommence.

A visit to the Chancellor with Lords colleagues before his statement in Parliament. He remains calm, courteous and lawyerly, even on death row. Then I prepare a public response to him. I panic that my stock of one-liners is drying up. I needn't have worried. Government appoints two non-doms to look after taxpayers' money. I couldn't have made it up. The media buzz continues even though the boil has now been lanced, leaving only a trail of pus.

When I reach home, I try switching off by switching on the telly. Bad mistake. The French Connection and Gene Hackman. Get to bed ridiculously late.

Tuesday and the government wants to scrutinise and pass the complex nationalisation bill before midnight. My party supports the bill but we worry about the details. George Osborne offers co-operation. Very affable despite my barbed comments about him the previous day. Thick skins needed in politics. Debate and amendments get to 11pm. Then chaos. What is Granite? What is Northern Rock? No one in government can tell us what we are taking over. After all, what's a few billion here or there? With late vote, I miss the last train to Twickenham and arrive home circa 2am. Greatly regretting Gene Hackman.

Next morning first thing, my Lib Dem Treasury colleagues meet. Sharp, highly motivated group of MPs, peers and researchers. Politics is a team sport, not for prima donnas. Wednesday is also Nick Clegg's turn in the spotlight. PMQs. Always a nerveracking battle against a wall of noise, especially for the Lib Dem leader. But Nick is doing well. Good content; good, confident delivery. I head off to King's Cross to lead seminar on Muslim finance. British sharia isn't about chopping off hands, but complicated financial instruments to avoid sin of usury. Ethical financing surely harmless: indeed, a good thing.

The evening is ring-fenced for my elder son Paul's birthday. Rachel and I take him to the Festival Hall to hear an amazing young Armenian violinist, Sergey Khachatryan, play Tchaikovsky. Paul is a fine musician himself who now mixes singing with family, teaching and good works. On the train home, he tells me about his trip to India's fourth world backwater, Bihar, where he was supporting a Buddhist project helping Dalits (untouchables). Since my first wife, Olympia, died, our links with India and her family have been weakened. Feel sense of wholeness that Paul is discovering India and reconnecting the extended family.

Northern Rock week ends, appropriately, with visit to Newcastle for Question Time. The audience contains people whose jobs are on the line. One man has also lost his life savings. Much damaged north east pride.

Tempted to play to the local gallery. But some home truths are necessary. The business will have to contract even under nationalisation. The taxpayers' money must be repaid.

Back to London on early train. Then, head back for weekly MP advice surgery. That is where we can make a real difference: off stage, out of the limelight.

The Cable CV

The Life Born York, 1943. Read natural sciences and economics at Cambridge. President of the Cambridge Union. PhD in economics from the University of Glasgow. First married Dr Olympia Rebelo, who died in 2001. They had three children. In 2004, married Rachel Wenban Smith. Keen ballroom dancer.

The Work In 1970, unsuccessfully fought Glasgow Hillhead for Labour, and later became a Glasgow councillor. Left Labour for the SDP in 1981. Academic and economist including chief economist at Shell 1995 to 1997, when he won Twickenham for the Lib Dems. Main economic spokesman since 2003; deputy leader of the Liberal Democrats since 2006. Acting leader between Menzies Campbell and Nick Clegg.